Sash-lock.



H. B. IVES.

SASH LOCK.

(Application filed Mar. 29, 1900.) (No Model.)

Patented. Oct. 2, I900.

2 Sheets-Sheet l.

H: B. 'I'VE'S.

SASH LOCK.

(Application filed Mar. 29, 1900.!

Patented Oct. 2, I900.

2 Sheets-Sheet 2.

(No Model.)

THE Norms PETERS co. Pnm'ouwa. wnsnmm'ou, n c.

ilwrren STATE PATENT Cement.

HOBART B. IVES, OF NEW HAVEN, CONNECTICUT.

SASH-LOCK.

SPECIFICATION forming part of Letters Patent No. 659,069, dated October 2, 1900. Application filed March 29, 1900. o'erial No. 10,6 '75. (N0 model.)

To all whom it may concern.-

Be it known that I, HOBART B. IVES, of New Haven, in the county of New Haven, and in the State of Connecticut, have invented certain new and useful Improvements inSash- Locks; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being bad to the accompanying drawings, in which- Figure 1 shows a plan view of my improved sash-lock, with the latch-hook shown in full lines as locked open and in dotted lines as swung back before it is moved back into the position in which it is locked open; Fig. 2, a similar view showing in full lines the latchhook in its sash-locking position and in dotted lines the latch-hook in the position from which the safety-springs will throw it fully open and into its locked-open condition; Fig. 3, a bottom plan view of the base with the spring-retaining washer removed from the pivot-pin and the parts in position as they are when the latch-hook is locked open; Fig. 4, a similar view with the parts in position as when the latch-hook has been swung to the middle point of its travel; Fig. 5, a plan view of the sash-lock with the turn-v ing knob or lever removed and its eccentricpin shown in section, the parts being in the same position as in Fig. 1; Fig. 6, a similar view showing the parts in position as in Fig. 2; Fig. 7, a view showing the base in plan and the guiding and locking flange on the base in section, such flange being shown in full lines in the position which it has when the latch-hook is locked open and in dotted lines in the position which it assumes when thelatch-hook is operating to lock the sashes; Fig. 8, a view of a section on line as a: of Fig. 1; Fig. 9, a view of a section on line y y of Fig. 2; Fig. 10, a detail perspective view showing the base and thelatch-hook separated; Fig. 11, a detail view showing, partly in section and partly in elevation, another arrangement of turning knob and pivot-pin; Fig. 12, a detail perspective viewof the form of pivot-pin shown in Fig. 11, and Fig. 13 a view of the keeper in front elevation.

Letters of like name and kind refer to like parts in each of the figures.

The object of my invention is to provide an improved sash-lock; and to this end my invention consists in the sash-lock and in the parts thereof constructed, arranged, and combined as hereinafter specified.

The special object which I have had in view in' inventing the present sash-lock has been to provide a device in which the latchhook shall move most easily and smoothly and be locked securelyin its open and closed positions and shall when it has been swung far enough open to clear the keeper be so acted upon by spring-pressure as to be thereby not only swung clear back away beyond a position where it could project so as to be liable to injure the cross-bars of the upper sash if the lower sash be raised, but also moved outward longitudinally into the position in which it is locked open.

The'result of my invention, as embodied in the sash-lock shown in the drawings and described hereinafter, has been to provide a sash-lock in which it is rendered impossible by accident or even by intent to leave the latch-hook swung clear of the keeper and yet in position to strike against or injure the cross-rail or cross-bars of the upper sash when the lower sash is raised. When the latchopened position and locked therein.

In the drawings, A designates the baseplate of my sash-lock, having the raised latch hook-supporting table and the usual attaching portions (1. (1, provided with screw-holes a a, by which the base can be attached to the cross-rail B of the lower sash. This base is preferably made, as shown, with the pendent flange a all around its edge adapted to rest upon the rail B and inclosing a recess within the base. Within such recess the base is provided with two pairs of downwardlyextending lugs a 01. a of, for a purpose to be described, preferably situated on the under side of the portions a a of thebase, and two other lugs a a extending downward from the main part or table of the base on opposite sides of the pivot-pin opening a in the base.

In the raised table portion of the base is the depression or recess a around the pivotpin opening a which extends through the bottom of such recess or depression. This recess or depression a is formed with the two ICO straightshoulders a a at right angles to each other, one of them, a being parallel with the front or inner edge a of the base, which in practice is when the base is secured on the sash-rail B parallel to the edge of the latter. At the outer end of each of these shoulders is a locking-notch a having one of its walls in line withthe face of the shoulder, as shown in the drawings. In order that the sides of each of these locking-notches a 0. may be fiat and abrupt, so as to engage squarely and positively the sides of the latch-hook flange, to be described, when such flange is slid longitudinally into the notch, I make such notches by punching rectangular holes through the base, this manner of making them rendering it most easy to give the notches just the shape wanted to fit the latch-hook-flange ends and to make the notch-walls perpendicular to the base without any incline or bevel, such as is apt to remain where it is attempted to make the locking notches or recesses by merely stamping down the raised or table part of the base. besides the shoulders a a the two curved guiding-surfaces a a, one extending around to the locking-notch at the outer end of the shoulder a and the other leading to the other notch. One curved surface, that leading to the latter notch, is nearer the pivot-pin opening a in the base than the other.

The latch-hook 0, having the body with the longitudinal slotc for the passage of the pivotpin of the turning knob, to be described, and the offset 0 from such slot at substantially a right angle to the latter, has the usual keeperengaging hooked part c and is, like the base, formed with a pendent flange around its edge, which rests upon the latchhooksupporting surface, which is the raised part or table of the base. At one side of the longitudinal slot 0 the latch-hook has the straight downwardly-extending longitudinal locking and guiding flange 0 parallel with the edge of the slot. Such fiange I form when the slot 0 is being made, the part to be removed to form the slot being cut loose from the body of the latch-hook at one side and both ends and bent downward into a position at right angles to the upper face of the latch-hook. This guiding and locking flange when the latch-hook is in place on base A projects down into the recess or depression a in the base, as shown in the drawings, Figs. 5 to 9, inclusive, and is adapted to engage the shoulders a a the notches a a and the curved surfaces a a on the base, as and for the purpose to be hereinafter described.

The turning knob D has the usual thumbpiece or handle d, the central pivot-pin d, which extends down through the longitudinal slot 0 of the latch-hook and the opening a in the base into the cavity in the base below the table or raised part of the latter, and the eccentric stud d engaging the offset a from the slot 0 of the latch-hook. This pivotpin (1, which is secured to the turning knob The large recess or depression a has,

so as to rotate therewith, has its portion just below the table of the base squared to re ceive a cam-piece d provided with a squared openingto fit such part of the pin, so that the cam-piece and pin must turn together. As shown, this cam-piece has the two flat parallel faces 01 d on opposite sides of the pinopening and two projecting portions (1 (Z also on opposite sides of the pin-opening, but on a line through such opening at right angles to the faces (1 d These portions (1 d have their opposite sides inclined toward each other, the points where such sides meet being preferably rounded slightly, as shown, to best resist wear. The form of the cam-piece is substantially a sharp ellipse, with the fiattened faces (1 d at opposite ends of its shortest diameter, making a double eccentric, with its parts of greatest eccentricity diametrically opposite each other. Situated within the cavity of the base, so as to engage this campiece (i are the two springs (Z d", arranged on opposite sides of such piece and extending along within the base in a direction substantially parallel with the front or inner edge a thereof. These springs, having their outer ends extending out between the pairs of lugs a a a a on the base, are held by such lugs pressed against opposite sides of the cam-piece d as shown. This cam-piece is fixed on the pivot-pin (1 so that the line of its greatest diameter is parallel with the handle or thumb-piece (l on the turning knob or substantiallyat right angles to a line from the pivot-pin to the eccentric stud d on the knob.

A retaining-washer E, having a squared opening to fit a portion of the pivot-pin (1', serves to retain the springs d d in their place in engagement with the cam-piece 01 such washer being kept on the pin by a heading down or upsetting of the extreme end of the latter below the washer, as shown, or, if desired, by a n utscrewed on the pin. The lugs a a, engaging the upper face of washer E, serve to keep it from binding on the springs 61 d so as to interfere in any way with their action. They are also useful in the assembling of the parts of the sash-lock, as they aid in holding the springs in place on the base before the cam-piece is placed on the pivot-pin between the springs and prevent too much heading down of the end of the pivot-pin to force the washer too near the top of the base.

While I prefer to have the pivot-pin with the knob D cast firmly upon its upper end, so as to insure a strong connection between pin and knob, I contemplate making the pin separate from the knob where desired, as shown in Figs. 11 and 12, the pivot-pin being provided just below its head d with'a squared portion (1 fitting in a correspondingly-shaped recess d inthe knob, the shank of the pin extending down belowthe portion (1 being constructed like that of the pin (1, already described.

The keeper F, which is to be attached by f, an upright portionf to be engaged by screws f f to the cross-rail B of the upper sash, is of the usual well-known construction used with what is known as the Ives form of sash-lock, having an attaching-base the shoulder of the hook of the latch-hook, so that the sashes will be drawn together as the latch-hook is moved longitudinally inward on the base after it has been swung outward against said upright portion of the keeper, and an overhanging arm f under which the latch-hook passes as it is swungin toward its sash-locking position and into engagement with the keeper. The under side of this arm is made inclined downward from its outer end, as indicated atf, so that if either one or both of the sashes should not be quite closed the latch-hook will as it is swung outward to bring it into engagement with the keeper engage this inclined under side of arm f and, bearing upward against it, cause the sashes to be cammed closed before the latch-hook comes into contact with the upright part f of the keeper.

The operation of my improved sash-lock is briefly as follows: With the parts in position as shown in Figs. 1, 3, 5, and 8,t he sash-lock is open and the sashes are free to be opened, as desired. When it is desired to lock the sashes, the handle or thumbpiece 01 is swung to rotate the turning knob D in the direction indicated by the arrow in Fig. 1. This causes the eccentric stud d on the knob by its engagement with the offset 0 from slot 0 in the latch-hook to cam the latch-hook longitudinally inward, because the engagement of the guiding and locking flange 0 with shoulder a and the notch a at the end of such shoulder prevents the swinging of the latch-hook around the pivotpin d until the outer portion of such flange has moved inward out of said notch. The other end of said flange then comes into contact with the curved surface a which leads to the other notch or and shoulder a and is stopped by such surface from farther longitudinal movement inward. This checks the inward drawing of the latch-hook, which, because of -the disengagement of the outer end of its flange from the locking-notch and the engagement of its other end with the curved surface, as just above described, is free to swing around pin 01, and does so swing, under the action of the stud d engaging the offset 0 in the latch-hook. This swinging of the latch-hook continues until the outer end of the latter is swung out into position to engage the keeper, when the flange 0 having passed off of the curved surface a along which it has been passing, comes in contact with the shoulder a which stops its swing and that of the latch-hook with the rear or outer end of the flange in line with the notch a at the end of such shoulder. The latchhook being thus held from swinging and left free to move longitudinally outward to carry its flange end into the locking-notch is so moved by the camming action of the eccentric stud dfiwhich engages and rides along the outer or rear side of the offset 0, until it takes the position shown in Fig. 6 and the parts of the sash-lock are in position to lock the sashes together, as indicated in Fig. 2. The latchhook is now positively held, as drawn inward, by the engagement of the eccentric stud with the rear side of ofifsetc' where that coincides with the end of slot 0, and is securely locked from being swung open around the pivot-pin by the engagement of the outer or rear end of the flange c with the lockingnotch a into which it has been moved. Swinging of the turning knob D in the other direction first causes the eccentric stud to cam the latch-hook longitudinally outward until the flange c is disengaged from the notch a in which it has been seated, and

comes into contact with the curved guidingsurface a which leads to the notch a at the outer end of shoulder CH. The engagement of the stud d with the offset 0 then swings the latch-hook outward and backward to disengage it entirely from the keeper and bring it around into the position indicated by dotted lines in Fig. 1. Here, having swung enough to take its hook entirely back of the edge of the sash-bar, the latch-hook, being prevented from swinging back farther by the engagement of its flange c with the shoulder ct" and being left free only to move outward under the pressure of the stud d against the side of the offset 0 is slid longitudinallyout- Ward, so that the flange enters the lockingnotch at the outer end of shoulder a with the result that the flange and the latch-hook cannot be wung inward again around the pivot-pin (1, because of the holding of the flange end by the notch which has received it. The latch-hook is thus locked open until it has slid inward longitudinally again. The latch-hook is when the sash-lock is open normally held in this locked-open position by the action of the springs d 01 which then engage and press against the flat faces (1 d at opposite ends of the shortest diameter of the cam-piece d in the pivot-pin d. The stress of these springs upon the cam-piece tends then to hold the cam-piece, and consequently the turning knob D, from being turned out of the positions which they occupy in Figs. 1 and 3, so that the eccentric stud 01'' holds the latch-hook forced longitudinally outward with its flange 0 locked in the locking-notch a at the outer end of shoulder a". The latch-hook cannot then be by accident swung around to carry the nose of its hooked portion beyond the inner edge of the sash. To so swing it, it is necessary to turn the turning knob D against the stress of the springs 61 d upon the cam 01 so as to first draw the latch-hook longitudinally around to release its locking-flange from the locking-notch in the base and then swing the latch-hook about the pivot-pin 01. Such turning is resisted by the springs d d", which are bent outward in opposite directions by the projecting eccentric-arms of the cam-piece (l the inclined sides of which, riding over the springs, cam them outward. If the turning knob be released before the latch-hook has been swung outward far enough to carry it under the keeper-arm, the pressure of the springs upon the inclined sides of the cam-piece will at once rotate such piece, and consequently the turning knob, back again to cause the latch-hook to be swung open and slid into its locked-open position again. The campiece does not reach the position shown in Fig. t--that is, the ends of its projecting arms resting squarely against the respective springs d duntil the turning knob D has been swung far enough to carry the latchhook partly under the overhanging arm f of the keeperF, so that the raising of the lower 'sash or lowering of the upper sash to any considerable extent is prevented. When the latch-hook is in the position shown in dotted lines in Fig. 2that is, so as to just clear the keeper-armf -the cam-piecehas the position shown in dotted lines in Fig. t, so that the stress of the springs (Z (If, being brought to bear on inclined faces of the cam-piece arms, will turn such piece and the knob to throw the latch-hook back and into its locked open position, as just above described. After the knob has been turned to carry the latch-hook under the arm of the keeper and turn the campiece to carry its spring-engaging arms forward beyond the position shown in full lines in Fig. at the springs d d, acting then upon the rearward inclined sides of cam-piece arms, will act to turn such piece to continue the swing of the latch-hook toward its sash-locking position and cause the knob to cam the hook longitudinally rearward to carry its flange 0 into the notch (1 which is to lock thelatch-hookinitssash-closingposition. By their action upon the cam-piece the springs will then act to hold the turning knob in the position shown in full lines in Fig. 2-that is, so as to keep the latch-hook held positively locked in its sash holding and locking position. With the springs acting as described the turning knob is not liable to be by accident left in or turned into position to fail to hold the latch-hook drawn and held positively inward, for the springs would at once cause the knob to turn from such position to carry its eccentric stud 61 around so as to lock the latch-hook inward, as shown in Fig. 6.

It will be seen from the drawings and the above description that my sash-lock cannot be left in condition to have its latch-hook projecting beyond the edge of the lower sashrail so as to strike and injure the cross-bars ortop railof the upper sash if thelower sash is raised or to have its latch-hook capable of being moved from its sash-locking position by anything but rotation of the turning knob by power applied for such purpose to the latter. The action of the spring mechanism shown and described is such as to always insure not only the full outward swing and locking open of the latch-hook when the latter has been swung to any point and from under the overhanging arm f of the keeper, but the full inward swing of the latch-hook and its locking in closed position when the latch-hook has been swung to a certain point under the keeper-arm. In my sash-lock the latch-hook when moved to unlock the sashes and have them free to be opened cannot be by accident or design left so as to project beyond the sashrail and strike orinjure the cross-bars of the upper sash as one or the other of the sashes is being opened. When open, the sash-hook is always sure to be fully open and the latchhook is certain to be not only swung fully back out of the way of the rails of the sash which carries the keeper, but positively looked as so swung.

I desire it to be understood that while I prefer to make the cam-piece d with two diametrically-opposite spring-engaging arms and the two flat faces (Z d to act in conjunction with the two springs d d", as shown and described, I contemplate using instead, where desired, only one spring and making the campiece correspondingly with only one projecting spring-en gaging arm and flat face d The double spring and cam-piece construction has been found preferable, however, as insuring the easier, more certain, and quicker rotation of the turning knob to actuate the latch-hook as described.

The latch-hook C, I prefer to make by stamping the same from thick sheet metal, so as to form the described and shown downwardlyextending flange around its edge, the offset 0 being punched out and the slot 0 being formed by punching downward the flange c, the punching of the latter being so done that the part forced down to leave the slot in the latch-hook body is only cut loose from the latter at one side and the two ends and is at its other side integral with or attached to the latch-hook body. The guiding and locking flange so formed on the latch-hook has been found to be especially strong and stiff and well adapted to act in conjunction with the shoulders 60 a and locking-notches a a on the base, so as to lock the latch-hook most strongly in its open and closed positions without any danger of bending the flange to interfere with the operation of the look even after long-continued practical use.

Having thus described my invention, what I claim is 1. A latch-hook for sash-locks having the longitudinal slot, the offset from such slot, and the downwardly-extending longitudinal guiding and locking flange at one side of the slot, such slot being formed by forcing down a portion of the latch-hook body to form the flange, substantially as and for the purpose described.

2. In a sash-lock, in combination with a base having a recess with a guiding-shoulder, a locking-notch, and a curved guiding-sur- LJI face, a lat ch-hook having a longitudinal slot and a longitudinal downwardly-extending flange along one side of such slot, a turning kn ob having a pivot-pin passing down through the latch-hook slot into the base, and cam connections between the knob and the latchhook to cause the latch-hook, as the knob is turned, to swing to carry its flange around over the curved surface on the base, and then to move longitudinally to carry the end of the latch-hook flange into the notch, substantially as and for the purpose described.

3. In a sash-lock, in' combination with a base having a recess with the two guidingshoulders, a locking-notch at the end of each guiding-shoulder, and the two curved guiding-surfaces, eachleading to one of the locking-notches, a latch-hook having a longitudinal slot, an offset from such slot, a longitudi nal guiding and locking flange along one side of the longitudinal slot, extending down into the recess in the base, a turning knob having an eccentric stud and a pivot-pin extending from the knob down through the slot in the latch-hook and into the base, substantially as and for the purpose described.

4. In a sash-lock, in combination with a base having a recess with the two guidingshonlders substantially at right angles to each other, a locking-notch at the end of each shoulder, and the two curved guiding-surfaces, astamped latch-hook having the longitudinal slot and the offset therefrom, such slot being formed by partly cutting away a portion of the body and bending such portion downward to form a longitudinal guiding and locking flange on the latch-hook, to extend down into the recess in the base, when the latch-hook is in place on the latter, and a turning knob, having the pivot-pin extending down through the slot in the latch-hook and into the base, and the eccentric stud to engage the offset from the latch-hook slot, substantially as and for the purpose described.

5. In a sash-lock, in combination with the base having a recess provided with a guidingshoulder, a recess formed at the end of such shoulderby punching a hole through the base, and a curved guiding-surface, a latch-hook having a guiding and locking projection ex tending down into the recess in the base, and a longitudinal slot, a turning knob, a pivotpin for the same extending down through the slot in the latch-hook and into the base, and cam connections between the knob and latchhook, substantially as and for the purpose described.

6. In a sash-lock, in combination with the base having a recess provided with two shoulders at an angle to each other, a lockingnotch at the outer end of each shoulder, each formed by punching an opening through the base, and the two curved guiding-surfaces each leading around to one of the lockingnotches, a latch-hook having a guiding and locking projection extending down into the recess in the base, a longitudinal slot and an offset therefrom; a turning knob having the eccentricstud and the knob pivot-pin extending down through the longitudinal slot in the latch-hook and pivotally connecting the knob with the base, substantially as and for the purpose described.

7. In a sash-lock, in combination with the swinging latch-hook, and a suitable base, a turning knob made movable with reference to the latch-hook, connections between the knob and the latch-hook, for actuating the latter, as the knob is rotated, a pivot-pin pivotally connecting the knob with the base, and spring mechanism acting upon and transmitting power through the knob to complete the operation of the latch when the knob has been turned partly around in one direction, substantially as and for the purpose described.

8. In a sash-lock in combination with a latch-hook having both rotary and rectilinear movement and a suitable base, a turning knob made movable with reference to the latch-hook,connections between the knob and the latch-hook for actuating the latter as the knob is rotated, a pivot-pin connecting the knob with the base, and spring mechanism acting upon and transmitting power through a part turning with the knob to complete the operation of the latch-hook through the knob when the knob has been partly turned in one direction, substantially as and for the purpose described.

9. In a sash-lock, in combination with the latch-hook and a suitable base, a turning knob made so as to turn with reference to the latch-hook, connections between the same and the latch-hook for actuating the latter as the knob is rotated, a pivotpin turning with the knob and pivotally connecting the latter with the base, an eccentric cam-piece on the pin and turning therewith, and a spring engaging such cam-piece, substantially as and for the purpose described.

10. In a sash-lock, in combination with the latch-hook and a suitable base, a turning knob made so as to turn with reference to the latch-hook,con nectionsbetween the same and the latch-hook for actuating the book as the knob is turned, a pivot-pin turning with the knob and pivotally connecting the latter with the base, a two-armed eccentric cam-piece on the pivot-pin and turning with the same, and the two springs suitably supported independent of the knob and latch-hook and engaging the cam-piece, substantially as and for the purpose described.

11. In a sash-lock, in combination with a swinging and reciprocating latch-hook, and a suitable base, a turning knob, eccentric connections between the knob and latch-hook, a pivotal connection between the knob and base, engaging guiding and locking means on the latch-hook and base, whereby the latchhook, as it is actuated by the turning of the knob, is first caused to swing around and then to move longitudinally to bring the locking devices into operation, and spring mechanism acting to complete the turning of the knob, when it has been partially turned to actuate the latch hook, substantially as and for the purpose described.

12. In a sash-lock, in combination with a swinging and reciprocating latch-hook, having a longitudinal slot, and a suitable base, a turning knob,a pivot-pin for the latter extending down through the slot in the latch-hook, and pivotally connecting the knob with the base, eccentric connections between the knob and latch-hook, engaging guiding and locking means on the base and latch-hook, whereby the latter as it is actuated by the turning of the knob is caused to swing about the pivotpin and then to move longitudinally to bring the locking device into operation, and spring mechanism actin to complete the turning of the knob, when it has been partially turned to actuate the latch-hook, substantially as and for the purpose described.

13. In a sash-lock, in combination with a swinging and reciprocating latch-hook having a guiding and locking projection, and a base having a surfaceto engage such projection and guide it in a curved path, and an offset or recess into which the projection on the latch hook is moved by the longitudinal movement of the latch-hook, after the projection on the hook has left the guiding-surface on the base, a turning knob, eccentric connections between the knob and latch-hook to cause the latter to swing to carry its guiding projection along the surface on the base, and then move longitudinally to carry the projection into the offset or recess on the base, a cam-piece turning with the knob, and a spring engaging such piece so as to turn the knob, substantially as and for the purpose described.

12L. In a. sash-lock, in combination with a base having a curved guiding-surface and a IOCklUg-IIOILCll, the latch-hook having a projection to engage such surface and notch and a longitudinal slot, a turning knob pivotally connected with the base by apivot-pin turning with the knob and passing through the slot in the latch-hook, such knob having an eccent.ricallyarranged stud engaging a way in the latch-hook, a cam-piece on the pivotpin and turning with the same, and a spring engaging such piece, so that its pressure thereon tends to swing the knob, to cause the latch-hook to be swung and then moved longitudinally to bring its projection into the locking-notch, substantially as and for the purpose described.

15. In a sash-lock, in combination with a suitable base, a latch-hook and the turning knob for actuating the same, made movable with reference to the latch-hook and having a pivot-pin turning with itand pivotally connecting it with the base, connections between theknob and latch-hook, whereby the former actuates the latter, a cam-piece on and turning with the pivot-pin, and a spring'engaging the same, substantially as and for the purpose described.

16. In a saslrlock, in combination with a suitable base having a curved surface and a locking-notch at. the end thereof, a swinging and sliding latch-hook havinga guiding and locking projection, and a longitudinal slot, a turning knob having an eccentric stud engaging a way in the latch-hook, a pivot-pin turning with the knob and pivotally connect- .ing it. with the base, an eccentric cam-piece on the pin and turning therewith, and a spring pressing against such cam-piece, sub stantially as and for the purpose described.

17. In a sash-lock, in combination with a suitable base having a shoulder and a locking-notch, a swinging and sliding latchhook havinga projection and alongitudinal slot, a turning knob having an eccentric stud engaging a way in the latch-hook, a pivot-pin turning with the knob and extending therefrom through the slot. in the latch-hook and into the base, a two-armed cam-piece on and turning with the pivot-pin, and two springs on opposite sides of such piece pressing against the latter, substantially as and for the purpose described.

18. In a sash-lock, in combination with the base having the two shoulders at an angle to each other, and the two locking-notches at the ends of the respective shoulders, the latch-hook having the longitudinal slot, and a guiding and locking projection, the turning knob having a pivot-pin turning with it, extending down through the slot in the latchhook and into the base, and an eccentric stud engaging a way in the latch-hook, a twoarmed cam-piece on and turning with the pin, 

